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# Default Values
In Java, different types of variables have different default values when they are not explicitly initialized. Here are the default values for each type:
1. **Primitive Data Types**
* `byte`, `short`, `int`, `long`: `0`
* `float`, `double`: `0.0`
* `char`: `'\u0000'` (null character)
* `boolean`: `false`
2. **Reference Data Types**
* For reference types (objects), the default value is `null`, meaning they do not refer to any object in memory.
3. **Local Variables**
* Local variables must be explicitly initialized before they are used. They do not have default values. **Compilation** error will occur if not initialized and tried to use.
4. **Static and Instance Variables**
* If they are not explicitly initialized, they are automatically initialized with their default values. **Non-static - Non local variables will also be initialized.**
```java
public class Application {
static int i1;
static Integer i2;
public static void main(String[] args) {
System.out.println(i1); // 0
System.out.println(i2); // null
}
}
```
---
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